Humidifying system for mobile vehicles

ABSTRACT

A container of water is mounted on a motor vehicle and a means for dispensing that water into a passenger compartment of said vehicle is provided. The water will be delivered in the form of vapor. An electrical circuit is formed with a humidity sensing device within the passenger compartment for purposes of actuating the vapor forming and dispensing apparatus. When actuated, water is permitted to flow by gravity from the water container to a heating vessel, where the vapor is formed, from which the vapor may flow through a valved outlet tube to a vehicle heating duct.

This application is a division of application Ser. No. 258,642, filedApr. 29, 1981, now U.S. Pat. No. 4,346,048.

BACKGROUND OF THE INVENTION

The value of humidifiers in millions of American homes and offices iswell known for preventing dry skin and noses, as well as an aid topreventing contraction of certain respiratory diseases. However, thereare probably twice as many automobiles, trucks, and other conveyances asthere are homes. Yet, no humidity system to alleviate this dry conditionhas been offered for cars, trucks, and other mobile units. A person mayride in a dry oven-type heated compartment in winter months where therelative humidity is often 10 percent or less moisture than in theSahara Desert. There are many truck drivers who spend eight hours, orso, in such an atmosphere during their daily working periods.

A typical experiment verifies this dry condition. A humidiquideindicator placed in a passenger car in the winter months when theoutside temperature is between 20° F. and 30° F. may indicate a relativehumidity of between 30 and 40 percent. The car is driven for fiftyminutes with the car heater temperature set at 72° F. The aircirculating through the car heater now shows the relative humidity to bedown to 10 to 15 percent.

Repeating the same experiment while adding moisture to the car by meansof a hydrometeor, the humidiguide indicator may be kept at about 40percent relative humidity.

The surprising thing, which has probably kept inventors from offeringsuch a system, is that one would expect the windows to fog up, but theydo not, due to the high volume of air curculating through the heaterduct system and the allowable moisture at a given temperature. At abarometric pressure of 30 inches of mercury and a temperature of 72° F.,the weight of moisture necessary to produce 40 percent relative humidityis only 3.2 grains of moisture per cubic foot. In layman's terms, thisis less than seven thousandths of an ounce.

All currently available inexpensive humidity indicating instruments havea certain lag response time; however, as one can imagine, as in theexample given, if it takes 50 minutes of 72° F. circulating air toreduce the indicating humidiguide to 10 percent relative humidity, themoisture replacement necessary to meet the aim of this invention is nota large quantity. A water dispensing container of one liter wouldprobably meet most needs to provide a sufficient period of time beforerefilling.

The novel apparatus of the instant invention may be installed in amobile vehicle in either one of three different ways. These threemethods show how a controlled quantity of water vapor can be maintainedto satisfy a set relative humidity in a vehicle, either by means ofevaporation using one of several hot areas of the vehicle; use of a unitheater powered by battery wattage; or by a mechanical pressure releasesystem using a D.C. motor. To meet these aims, a number of objectivesare claimed as follows:

The principal objective of the present invention is to provide acontrolled relative humidity system for mobile vehicles such as cars,trucks, buses, trains, and the like.

Another objective is to provide a suitable water vessel with integralcontrolled water and vapor valve inlets and outlets.

Another object of the invention is to provide a controlled moisturedispensing system that discharges vapor directly into the conventionalheating duct of the vehicle.

Another objective is to provide a controlled flow of water from a mainliquid container to a smaller vessel located in one of the hot zones ofthe vehicle for the purpose of converting water to steam or vapor.

Another objective is to provide a simplified modular system using abattery heater for converting the controlled flow of water to vapor.

Another objective is to include an electrical circuit and humiditycontrol which holds the desired preset percentage of relative humidityin the driver and/or passenger compartments.

Another objective is to provide an electrical and humidity controlcircuit which functions only in the "on" position when relatedconditions of all associated elements are in the correct mode ofinfluence.

Another objective is to provide a portable, completely self-contained,automatic moisture regulating and dispensing unit that can be pluggedinto the cigarette lighter receptacle of the vehicle.

Another objective of my invention is to provide an even more simplifiedself-contained, portable system for controlling relative humidity in avehicle, that also gets its power from a plug-in arrangement using thecigarette lighter receptacle, and vaporizes moisture by a motor-drivenpressure pump.

To sustain a relative humidity in the cab of a truck or car at between30 and 40 percent is the objective of my invention to provide betterhealth and comfort for winter driving. With this objective in mind,details of my humidifying system for mobile transportation units ishereby disclosed. Other objectives of the invention will become apparentas one studies the description of the preferred embodiments and therespective diagrammatic drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a section of the main operating moisture dispensing unit andcontrol valves of my invention;

FIG. 2 is a schematic representation of the electrical and moisturesensing circuit that controls the moisture dispensing unit, shown inFIG. 1;

FIG. 3 is an exploded view of a water heating container attached to amotor block according to this invention;

FIG. 4 is a partial sectional view of an existing vehicle heating ductshowing a heating radiator and fan and including a vapor hose connectionduct at the top right according to this invention;

FIG. 5 is a cross sectional view of an alternative humidity control unitwhich is portable and powered by a connection with the cigar lighter;

FIG. 6 is a circuit diagram for the portable unit of FIG. 5;

FIG. 7 is an elevational view, partially in section, of an alternativeembodiment of my invention as illustrated in FIG. 1; and

FIG. 8 is a circuit diagram for the unit of FIG. 7.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a partial sectional view of a water container 1 with aremovable seal lid 2. The container is designed to store water in thewinter season and anti-freeze should not be added; accordingly the unitand its associated water conducting components would be made of aflexible material such as polyvinylchloride to accomodate possiblefreezing and thawing without damage to the equipment. The watercontainer may be located in any convenient area of the vehicle, butpreferably under the hood, in the engine compartment. The container 1normally is filled with water 3 and is generally supported in place by abracket 4 and held in place by at least two screws 5. A rubber stopper 6in the drain port 7 of the container allows the unit to be drained foreasy cleaning or any other desirable reason.

Three appendages 8, 9 and 10 extend horizontally from container 1 andpreferably are an integral part of the container, but could be separateunits. Appendage 8 comprises an L-shaped duct housing a valve to controlthe flow of water vapor and is installed with a press fit valve seatcylinder 11, a seal carrier adapter 12, and a rubber seal disk 13. Sealdisk 13 is held against valve seat cylinder 11 by means of a helicalcompression spring 14. Valve actuator rod 15 is attached to seal carrieradapter 12 by a roll pin 16. An "O"-ring seal 17 keeps vapor fromescaping around valve actuator rod 15. Flexible tubing 18 is attached tothe inlet 19 of appendage 8 and flexible tubing 20 is attached to theoutlet 21. Vapor from another source, to be explained later, entersinlet 19 and when the adapter 12 is retracted, exits through outlet port21.

Appendage 9 houses a solenoid 22 held in place by set screw 23. Solenoidor actuator 22 has a special plunger 24 attached to valve actuator rod15 by roll pin 25. Humidity sensing units control the operation ofsolenoid 22 which, in turn, opens and closes the valve in appendage 8.

Appendage 10 comprises a duct for the exit of water 3 from container 1and a valving arrangement controlled by solenoid 22 operates to stop andstart gravity flow. A valve stem 27 has initially been inserted through"O"-ring 28 which prevents leakage around the stem at port 29. Locknut32 secures adjusted valve stem 27 in place after it has been threadedinto plunger 24.

The lower end of stem 27 has a circular rubber seal tip 33 which sealsport 26 when plunger 24 is in the unenergized position. A hose bib 34 isthreaded into the duct of appendage 10 and a hose 35 is pulled over thehose bib to conduct water when the valve is open.

FIG. 2 illustrates the control circuit which actuates the humidifyingsystem of FIG. 1. In order for the system to function, heater switch 36to heater system 37 must be turned on. Humidity switch 38 must also bein the "ON" position. A humidity sensing device 39 may be located withinthe passenger compartment of the vehicle and may be any one of severalmoisture sensing switches now available on the market. When the relativehumidity is below a pre-set level of desired humidity, preferably 35 to40 percent, the switch of the humidity sensing device transfers to the"ON" position.

The temperature of a water heating vessel, shown in FIG. 3, must be upto a pre-set temperature (about 175° F.) before thermistor 40 will passcurrent. When the four switches mentioned are closed, solenoid 22 willoperate causing plunger 24 to descend thereby opening water valve 33 andvapor valve 13.

Turning now to FIG. 3, a lid 41 with locking ring clamps 42 and 43 isdesigned to be locked on top of vessel 47 and a seal ring 45therebetween prevents vapor leakage. The top of the lid 41 has a vaporoutlet port 44 over which a vapor outlet tube 18 is attached--this isthe opposite end of tube 18 shown attached to inlet port 19 of appendage8, FIG. 1.

Locking ring clamps 42 and 43 are slipped over the inclined planes 48and 49 of the locking ears 50 and 51, respectively, and are held inplace in undercut grooves juxtaposed to the sides of vessel 47.Thermister 40, mounted in the bottom of vessel 47, is a part of thecontrol circuit as explained in the description of FIG. 2. Insulatedelectrical terminals 52 and 53 are connected to thermister 40, whichconducts current only when the water heating vessel reaches apredetermined temperature (175° F.). Water entrance hose 35 supplieswater to water heating vessel 47 through port 46--this is the oppositeend of the same tube 35 shown attached to water outlet port hose bib 34of appendage 10, FIG. 1. Water heating chamber vessel 47 is attached toan appropriate vehicle hot zone 55 by means of flange 56 with nut 57.

The representative conventional heater duct 58, FIG. 4, also shows fanmotor 59 and fan 60 which normally circulates vehicle compartment airthrough the heater 61. Conventional heater temperature circulating fluidports 62 and 63 are shown attached to the heater for clarity but are nota part of this invention. Entrance port 64 leads into duct 58 downstreamof heater 61. Attached to port 64 is vapor inlet tube 20--this is theopposite end of the same vapor outlet tube 20 shown attached to outletport 21 of appendage 8, FIG. 1, and is the only attachment necessary tothe conventional heater system of the vehicle.

It can now be seen that as the control switches of FIG. 2 close,solenoid 22 of FIG. 1 operates to open the water metering valve 33,allowing water to pass to water heater vessel 47, FIG. 3. Means are notshown in the drawings to prevent the overflow of heater vessel 77 whenvalve 33 is open as shown in FIG. 1. Means for accomplishing the obviousneed to prevent overflow could be achieved in innumerable ways whichwould be obvious to those having ordinary skill in the art. Water invessel 47 is heated into vapor, transferring through lid 41, tube 18,thence to inlet port 19, appendage 8, FIG. 1. Valve port 21, now beingopen by action of solenoid 22, allows vapor to pass through tube 20 tothe vehicle heater duct 58 at inlet port 64 providing moisture to theexisting conventional heater air circulating system. When the humiditysensor 39 is satisfied in reaching the desired percentage of pre-setlevel of relative humidity, the humidity sensing device deenergizes theoperating solenoid 22 and vapor supply to the humidifying systemdiscontinues until the level of relative humidity goes below the pre-setpoint. Obviously, a slow leak may be provided at valve 13 to preventexcessive pressure buildup in the system between vessel 47 and valve 13when water in vessel 47 is hot and the humidity is above the presetlevel and valve 13 is closed.

FIGS. 5 and 6 show a much simpler and easier to install portable versionof the invention that can be plugged into a cigar lighter of a car ortruck. The housing is made up of three sections; namely, the reservoir65, lid 66, and vapor shroud 67. The shroud and reservoir may be formedintegrally, separately or a combination of both. Obviously, the way itis formed and located will not affect the operation of the apparatus. Itis shown as housed in a single container because it is the preferredembodiment.

Shroud 67 has an integral duct 74 leading to an extension hose 75, ifrequired. The duct 74 may simply discharge water vapor directly into thepassanger compartment if it is physically located in the passengercompartment. The solenoid 22 and metered water valve 33 are the same aspreviously described in FIG. 1. Vapor spout 74 extends from aperture 76in the top of water pan 77. Pan 77 is located atop a housing 78 whichcontains a heater coil 80 and a heat control unit 83. Said heater coilis mounted on insulator inserts 81 and 82. A drain plug 85 may beinstalled similarly to plug 6 in FIG. 1.

FIG. 6 is the control circuit of the simplier portable humidifier ofFIG. 5, in which cigar lighter receptical 90 supplies D.C. voltage tothe humidity sensor switch 39. Positive D.C. line 91 out of sensorswitch 39 runs in series through the bimetal temperature control unit,thence to solenoid 22 and heater 80. The negative D.C. line 92 isattached to the opposite side of heater 80 and solenoid 22.

When humidity sensor switch 39 is in the "ON" position, calling formoisture, solenoid 22 opens valve 33 allowing a quantity of water tofill water pan 77 through spout 93. The water level never rises higherthan the lower end of water spout 93 because container 65 is air tightand unless air bubbles up through spout 93 into container 65 a vacuumwill form which will hold the water in place is the manner of aconventional water bottle of a drinking fountain in many businessoffices.

Heater 80 brings the water in chamber or pan 77 to a controlledtemperature of 160° F. to 170° F., causing vapor moisture to rise out ofvapor spout 74. When humidity sensor switch 39 is satisfied, as to apre-set level of relative humidity, current is discontinued and thehumidifier ceases to function until more moisture is required.

FIG. 7 is an even more simplified version of the invention in which themain container water supply source 94 includes lid 95. D.C. motor 96 isattached to the under carriage of water container 94 by two self-tappingscrews 97. When the system calls for moisture, motor 96 rotates cam 98which is attached to motor shaft 99 by roll pin 100. Cam 98 drivespistion 101, which is returned and kept in continuous contact with cam98 by compression spring 102. Piston 101 is installed with cam follower103 which is held in place and allowed to rotate around pin 104. Piston101 has a cup-shaped rubber seal insert 105 which reciprocates within achamber cylinder 106 as a part of piston 101 and serves to provide awater tight seal with the interior surface of cylinder 106. Seal cap 107and "O"-ring 108 complete the cylinder-piston assembly.

Unidirectional platypus intake valve 109 is held in place by springwasher 110 and retainer ring 111. On the back stroke (to the right inFIG. 7) of piston 101, water is sucked into cylinder 106 throughunidirectional platypus valve 109. On the compression stroke of piston101 water is forced up passage tube 112 to back pressure valve 113,which is held spray tight by cap 114. Threaded inset 115 is a bondedseparate section for convenience of manufacture.

On the back stroke of piston 101, back pressure valve 113 closes outletpassage tube 112. On the forward pressure stroke of piston 101 valve 109closes and valve 113 opens allowing water to pass through orifices 116of valve 113. The tighter cap 114 is forced against orifices 116, thefiner the vapor spray through orifice 117. The spray from orifice 117will flow directly into the passenger compartment. Obviously, cap 95will allow air leakage into container 94 to prevent a vacuum when wateris withdrawn through valve 109.

FIG. 8 is the control circuit for the above portable relative humiditysystem unit. Again 90 is the receptacle which may be plugged into thevehicle cigarette unit, relative humidity control switch 39 keeps thevehicle at a pre-set percentage of moisture, 96 is the D.C. drive motor.

I claim:
 1. Apparatus for controlling the humidity of the passengercompartment of a vehicle, in combination:a container for holding water,said container including an upper opening for filling purposes and twolower openings for discharge purposes, when in operative condition:(a)the upper opening being closed by a lid which seals the container influid tight condition, (b) the first of said lower openings being adrain opening having means therein to prevent both water fromdischarging and air from entering, and (c) the second of said loweropenings leading into a passage, said passage including a valve seat, avalve member for sealing against said seat in fluid tight arrangement,said valve member being mounted on a common stem with a reciprocalplunger, said plunger being a part of an actuator, said actuator beingcontrolled by a humidity sensing device and powered by electricalcurrent from the electrical system of said vehicle, a hose memberleading from the passage downstream of the valve seat to a port into aheating vessel the passage, hose, port and heating vessel beingconfigured to allow water to flow by gravity from the container to thevessel and air to flow from said vessel to the container to relieve thevacuum formed by the discharge of water from the fluid tight containerwhen said valve member is in open position, a vapor outlet tube leadingfrom the vessel to the interior of the passenger compartment wherebywater vapor generated by said heater will exit the vessel and flow tothe compartment until the humidity sensing device deactivates theelectrical system when a predetermined humidity level has been reachedin the compartment.
 2. The apparatus of claim 1 wherein the passage fromthe container to the hose member is generally L-shaped with the valveseat being located in the branch of the L-shaped not leading directlyinto the container,the branch of the L-shape which leads directly intothe container terminating at its outer end in an opening which, inoperative position, is sealed by a plug which is removable for cleaningthe passage.
 3. The apparatus of claim 2 including a second valve memberlocated in the vapor flow path from the vessel to the compartment,saidsecond valve member being coaxially connected with the first valvemember and on a common stem whereby opening of one valve member issimultaneous with the opening of the other valve member.
 4. Theapparatus of claim 4 wherein the second valve member includes meansforming a leak to allow vapor generated in the vessel to escape into thecompartment when the second valve member is closed to thereby preventexcessive pressure buildup when water is being vaporized in the vesselbut the humidity sensing device has closed the two valve members.
 5. Theapparatus of claim 4 wherein the vapor flow path leads from the vessel,past the second valve and into the vehicle heating ducts prior to itsdischarge into the passenger compartment.
 6. The apparatus of claim 1including a second valve member located in the vapor flow path from thevessel to the compartment,said second valve member being coaxiallyconnected with the first valve member and on a common stem wherebyopening of one valve member is simultaneous with the opening of theother valve member.
 7. The apparatus of claim 6 wherein the second valvemember includes means forming a leak to allow vapor generated in thevessel to escape into the compartment when the second valve member isclosed to thereby prevent excessive pressure buildup when water is beingvaporized in the vessel but the humidity sensing device has closed thetwo valve members.
 8. The apparatus of claim 7 wherein the vapor flowpath leads from the vessel, past the second valve and into the vehicleheating ducts prior to its discharge into the passenger compartment. 9.The apparatus of claim 2 wherein the vapor flow path leads from thevessel, past the second valve and into the vehicle heating ducts priorto its discharge into the passenger compartment.
 10. The apparatus ofclaim 1 wherein the vapor flow path leads from the vessel, past thesecond valve and into the vehicle heating ducts prior to its dischargeinto the passenger compartment.